pip not working on hombrew python 2.7 install

Question

I've installed python using homebrew and I can't invoke pip from the bash. I've tried amending my .bash_profile to include /usr/local/bin/python and /usr local/share/python to no avail.

When I use the bash command:

find / -name 'pip'

The only results I get are:

/Library/Python/2.7/site-packages/pip-1.5.6-py2.7.egg/pip
/Users/Ivan/Library/Caches/pip
/Users/Ivan/Library/Logs/pip
/usr/local/Cellar/python/2.7.9/libexec/pip
/usr/local/Cellar/python/2.7.9/libexec/pip/pip
/usr/local/lib/python2.7/site-packages/pip

None of which are an executable.

I don't really know where to point my $PATH as I can't find the pip executable. When I open

/usr/local/lib/python2.7/site-packages/pip

or

/usr/local/Cellar/python/2.7.9/libexec/pip/pip

I find the following files:

__init__.py         commands            operations
__init__.pyc        compat              pep425tags.py
__main__.py         download.py         pep425tags.pyc
__main__.pyc        download.pyc        req
_vendor             exceptions.py       status_codes.py
basecommand.py      exceptions.pyc      status_codes.pyc
basecommand.pyc     index.py            utils
baseparser.py       index.pyc           vcs
baseparser.pyc      locations.py        wheel.py
cmdoptions.py       locations.pyc       wheel.pyc
cmdoptions.pyc      models

None of which are an executable.

I would appreciate the help of anyone with more experience than me.

Edit: I tried the steps suggested by Marco:

Here are the results to the steps:

1. echo $PATH shows a few directories: /usr/local/bin:/usr/local/mysql/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/texbin:/opt/X11/bin:/usr/local/mysql/bin

2. which -a python returns: /usr/local/bin/python /usr/local/bin/python

nothing is returned for which -a pip

3. which python returns: /usr/local/bin/python

nothing is returned for which pip

4. ls -l $(which python) returns a single directory: lrwxr-xr-x 1 Ivan admin 33 17 May 08:59 /usr/local/bin/python -> ../Cellar/python/2.7.9/bin/python

ls -l $(which pip) returns several, including the python files that I showed in my original post

Solution 1

Generally, homebrew will install a formula into /usr/local/Cellar/formula and then place a link at /usr/local/bin/formula.

To make use of your installed formulae, make sure /usr/local/bin is in your $PATH. Show your $PATH by typing

echo $PATH

If /usr/local/bin is not in your $PATH, put this line at the end of your ~/.profile file.

export PATH="/usr/local/bin:$PATH"

Now, check what pythons are found on your OSX by typing:

which -a python

There should be one python found at /usr/bin/ (the Apple python) and one at /usr/local/bin/ which is the Homebrew python.

which python

will show you, which python is found first in your $PATH and will be executed when you invoke python.

If you want to know, where the executable is, show it by typing

ls -l $(which python)

This could look like this: lrwxr-xr-x 1 root wheel 68 7 Mai 13:22 python -> /usr/local/bin/python

This will work for pip as well.

If you show the results of this steps, we can probably help you much easier.

-- UPDATE --

You have /usr/local/bin/python linked to /usr/local/Cellar/python/2.7.9/bin/python. -> brew install python worked.

show, if pip is installed by typing

brew list python | grep pip

You should see

/usr/local/Cellar/python/2.7.9/bin/pip

If not, check, if there are links, which are not done with brew install. Told you something like this:

"Error: The `brew link` step did not complete successfully
The formula built, but is not symlinked into /usr/local"

To force the link and overwrite all conflicting files:

brew link --overwrite python

To list all files that would be deleted:

brew link --overwrite --dry-run python

** NO standard Apple /usr/bin/python **

link from /usr/local/Cellar/python/2.7.9/bin/python to /usr/bin/python

ln -s /usr/local/Cellar/python/2.7.9/bin/python /usr/bin/python

This is necessary for all python scripts beginning with #!/usr/bin/python. Especialy easy_install will fail, if link is not there.

Now, you are able to run

easy_install pip

Hope, you're making progress

Solution 2

If brew is managing your python install and pip is no longer symlinked (i.e. you type "which pip" and get no results) try this from your home directory:

brew unlink python && brew link python

Not sure if the old method works any more (it didn't on my machine).

Now confirm it does indeed point to your 2.7 installation with pip --version (it will list the python major version in the directory output).

Solution 3

Not really an answer to the original question, but if anyone ends up here because their Homebrew-installed python/pip are no longer working (i.e. python points to the system python and pip is not found) then the reason might be a recent (summer 2017) change in the way Homebrew installs and links python.

The solution is to add the following to ~/.bash_profile and/or ~/.zshrc:

export PATH="$(brew --prefix)/opt/python/libexec/bin:$PATH"

This will make python point to the brew version of python and also give you pip. See the caveats section under brew info python and https://github.com/Homebrew/homebrew-core/issues/15746 for more information

Solution 4

By default Homebrew provides pip via: brew install python. However you will then have two Pythons installed on your Mac, you can alternatively install it via:

sudo easy_install pip

To verify which files are installed with your Python package, try:

$ brew list python
/usr/local/Cellar/python/2.7.9/bin/pip
/usr/local/Cellar/python/2.7.9/bin/pip2
/usr/local/Cellar/python/2.7.9/bin/pip2.7
...

which should consist pip.

After installation you should symlink your formula's installed files by:

brew link python

which should create the right symbolic links (such as /usr/local/bin/pip pointing to your Cellar/python/2.?.?/bin/pip)

If you've permission issue, you may fix it by:

sudo chgrp -R admin /usr/local /Library/Caches/Homebrew
sudo chmod -R g+w /usr/local /Library/Caches/Homebrew

and make sure your user is in admin group (id -Gn $USER).

After fixing the permissions, do not use sudo when using brew command.

Then re-link it again:

brew unlink python && brew link python

To test dry-run, unlink and run: brew link -n python to see links of files which brew would link.

After linking is successful, make sure that your PATH system variable have /usr/local, if not, add:

export PATH=/usr/local/sbin:/usr/local/bin:$PATH

to your ~/.bashrc file.

If successful, your pip should work now.

View more solutions

Comments

[YoungPadawan]

Marco, thanks for your answer! Please see my original question for the results to the steps - I have added them in

[YoungPadawan]

Thanks for your answer kenorb! Part of the problem is that easy_install doesn't work for me either. In the bash I get: -bash: /usr/bin/easy_install: /usr/bin/python: bad interpreter: No such file or directory

[kenorb]

That means you don't have /usr/bin/python installed (which normally should be provided with OS X). So please try as suggested, which is: brew install python && brew link python, then add /usr/local/bin to your PATH.

[Marco M. von Hagen]

@YoungPadawan looks like you don't have Apple standard /usr/bin/python. This is not good, because many Python scripts start with #!/usr/bin/python. If there is no python, you get error messages like yours. Use brew link --dry-run python to check, what will be changed to your links when using brew link --overwrite python. We will get your pip running ;-)

[Marco M. von Hagen]

use brew link --overwrite --dry-run python to see, which files will be overwritten.

[YoungPadawan]

I don't think that brew install python && brew link python is putting python in /usr/bin. I'm seeing it in usr/local/bin, but I'm not seeing the symlink to pip there. I've unlinked and linked python as well, and nothing changes. It seems that the brew install and link isn't putting things where it should

[kenorb]

@YoungPadawan brew doesn't do anything with /usr/bin, but /usr/local/bin. Try: brew unlink python and dry-run: brew link -n python to list all the files which should be linked and check if pip is there. If yes, run again without -n.

[YoungPadawan]

I've ticked your answer because it led me down the right path, but in the end it was a permission issue. After installing I got a Warning: The post-install step did not complete successfully You can try again using brew postinstall python. I tried the brew postinstall python` command and it led me to a few files that I didn't have access to which I chowned. Now I can use pip! Thanks again

[YoungPadawan]

Thanks Kenorb, I've found a solution. In the end it was a faulty install due to permissions. I modified the permissions on a few files that brew was conflicting with and re-ran the installation and now everything works fine. There are more details in a comment to the question above. Thanks again for your answer, it was really helpful in getting me to the solution.

[David Pursehouse]

In my case the problem was The post-install step did not complete successfully due to error: could not delete '/usr/local/lib/python2.7/site-packages/pip/__init__.py': Permission denied. Manually deleting that file and then running brew postinstall python again fixed it.

[Robeezy]

nope, still doesn't work.

[Robeezy]

nope, none of this works, sorry bro.

[kenorb]

@Robeezy Ask a new question then, maybe your issue is somewhere else.